Development of the Indian ARJUN

Indian indigenous Arjun MBT development history is a facinating story of Indian quest to develop a formidable Tank.
The main battle tank MBT-80 which is now called MBT Arjun was conceived by the Indian Army after it realised the futility of its tanks mainly in desert conditions, during the 1971 war.

1972 – 1975

In October 1970 a symposium was held on the Indian Main Battle Tank (MBT) at Armoured Corps Center and School. It was attended by the representatives from Indian Army General Staff (GS), Defence Research and Development Organisation DRDO), Director General Quality Assurance (DGQA) and Department of Defence Production (DODP). The main aim of the symposium was to formulate GSQR for future Indian MBT.

The first draft of Qualitative Requirement (QR) was prepared by Armoured Corps Directorate and discussed with Vice Chief of Army Staff (VCOAS).

The first General Staff Qualitative Requirement (GSQR) was issued in August 1972 as QR No. 326 for the design and development of MBT. The QR 326 was not exhaustive and with regard to specifications but featured only skeleton specifications.

The design and development of MBT based on GSQR No. 326 was taken up by the Combat Vehicle Research and Development Establishment (CVRDE). The initial outlay of Rs. 15.50 Crore was sanctioned vide the Government of India (GOI) letter dated 02 May, 1974. Project Development Certification (PDC) of the project was 10 years from the date of sanction.

The MBT was to be designed around imported engine as the design and development experience to create a tank engine was not available within the time frame of the project. In 1974, DRDO had to take up design and development of a tank engine as Government of India could not import a tank engine because of political and other reasons.

DRDO prepared the system configuration of the tank. Indigenous engine hardware was assembled and motoring test commenced by 1979. Indigenous suspension and transmission hardware was ready for development test. The main 115mm armament was developed and trials were carried out for proof at Balasore ranges. The gun system and fire control system design was configured. One prototype hull in mild steel was fabricated to check the fitment and assembly.

In April 1978, the Indian Army called DRDO for a meeting for mutual discussions. The aim was to change the GSQR No. 326. A series of meetings between DRDO and Indian Army, chaired by VCOAS resulted in change in GSQR. The new GSQR bearing the number 431 was issued in August 1982.

The changes in the GSQR No. 431 were

a)Increase in width and weight
b)110/115mm gun was to be replaced with a 120mm gun.
c)Improved Sighting and Fire Control system.

Essentially it meant creation of entirely new design and systems. A sum of Rs. 56.55 Crores was obtained mainly to cater to cater to GSQR changes and price escalation due to inflation/ rise in import costs.

The PDC of the project was revised. The first prototype was to be built by October 1980 and subsequently 12 prototypes were to be developed, one in every 6 months.

The indigenous engine and transmission evaluation on dynamometer was carried out during 1979-81.

As already mentioned that the country had no experience in building an basic internal combustion engine. The tank engine development slipped as this engine was to be made after experimenting with basics of an internal combustion engine. Project of this scale was almost impossible for nascent Indian research laboratories. By this time, the western governments had shown willingness to supply the engines. A decision was taken to import a limited number of engines (also called “power packs”) from M/S MTU, Germany. For the fitment On Mark 1 (Mk 1) prototypes so as not to let the development schedule of the MBT slip.

Initially MTU supplied a 700hp engine for fitment trials and subsequently supplied 1100hp engine for prototypes. The MTU was also developing a 1400hp engine as per the specifications laid down by CVRDE.

The first prototype of the MBT was developed based on GSQR No. 326 of 1972 and No. 431 of 1982.

The prototype was subjected to limited technical trials by DRDO at Avadi and Jodhpur desert area.

Subsequently, few more prototypes were produced with different configuration by 1985.

In the initial development phase, suspension, running gear and other automotive systems were being evaluated with 1100 hp engine.

There had been significant enhancement in the battle tank technologies world wide and there was a possibility of these tanks being introduced in the Indian Sub Continent. This prompted Indian Army to change its GSQR and in November 1985, third GSQR No. 467 was issued. The changes in GSQR were:

a)More lethal gun of 120mm caliber.
b)Requirement of Fin Stabilized Armour Piercing Discarding Sabot (FSAPDS)
c)Development of Semi Combustible Cartridge cases and high energy propellant.
d)Integrated Fire Control System based on sight stabilized system with periscopic gunner sight.
e)Thermal Imaging system for gunner’s main sight for night fighting capabilities.
f)Provision of “Kanchan Armour” for enhanced immunity.

In addition following conditions were in the new GSQR:

•Manufacture of 23 Pre production Series (PPS) Tanks to enable full scale troop trials and after that smooth transfer technology (TOT) to a production agency.
•Setting of Armoured Fighting Vehicle (AFV) evaluation center and augmentation of infrastructure facilities.
•Realistic assessment of technical and user trial.
•Import of engines for prototypes and PPS.

The revised financial implication because of the new GSQR was Rs. 280.80 Crores which was issued in 1987. The GSQR escalated the cost of materials, stores and the import cost spiraled due to weakening Rupee.

The development of the tank was progressed with reference to the new GSQR. DRDO had to re – design the structure of chassis/ hull. The turret had to be designed again to cater to improved armour protection and a high power to weight ratio power pack. The MBT now also to feature Nuclear Biological and Chemical (NBC) warfare and protection system, Medium Fording capability, auxiliary power unit (APU), Laser Warning System (LWS) and Global Positioning System (GPS).

The period of 1985 – 1990 was significant in history of Arjun Tank for the progressive evolution of a number of systems through exhaustive field testing. A total of 12 Arjun Tank prototypes were built in order to prove the design, development and system integration of a number of systems through field testing.

The integration of first prototype with a proper 1400 hp engine was accomplished in 1989. During the automotive trials of the prototypes a total of 20,000 Kilometer run in various terrain. Arjun MBT covered 11000 kilometers in dessert terrain and 1000 kilometers in river bed terrain. The weapon system was also tested by firing 540 FSAPDS and 560 HESH.

The confidence of DRDO had built up with these prototypes and many improvements were made.

The first batch of 6 PPS tanks had got manufactured through Heavy Vehicles Factory (HVF) in Avadi, Bharat Heavy Electricals Limited (BHEL) and Bharat Earth Movers Limited (BEML), each two PPS tanks. Indent for manufacture of manufacture of 9 more PPS tanks by HVF was released to HVF in December 1992.

MBT Arjun was formally inducted into Indian Army in 1993 with these 6 tanks. The performance of PPS tanks were demonstrated to the Defence Minister, COAS and the members of the Parliament in February 1993.

The PPS tanks were put through grueling tests by the field formations covering several thousand kilometers of automotive runs on various terrains and firing hundreds of rounds per tank to establish the efficiency of the Arjun tank.

The status of the Arjun Tank was reviewed by the COAS in May 1994 and “bottom line requirements” were laid down. After the completion of the 1994 trials on MBT Arjun, a presentation was made to the COAS and he laid down “Imperatives” in August 1994.

All the additional 9 PPS tanks were handed over to Army progressively and the final handing over of the 9th PPS Tank to Army happened in 1996. The last PPS tank (i.e. XV) incorporating improvements as suggested by the Army and with add on features viz. APU, NBC, Medium Fording Capability was demonstrated to COAS and users at Avadi.

The PPS Tanks delivered to the Army during this period had covered 70,000 kilometers of automotive trials and fired 7000 rounds. The average kilometer run by a PPS tank was 4500 kilometers and 460 rounds fired from each tank.

DRDO addressed the bottom line requirements and imperatives as demanded by the COAS. The overall design of the Arjun Tank was cleared.

1995 – 2000

A set of dedicated trials as directed by the COAS was carried out during August – December 1995 successfully.

The Prime Minister P.V Narsimha Rao dedicated the MBT Arjun to the nation in January 1996.

The Army designated the XV PPS tank as the reference tank for production.

In the year 1997, 11 PPS tanks participated in Indian Army Exercise “AGNIR.ATI-t.” (A clarification on the name of the exercise is needed. It could be Exercise Agnirathi). 10 Arjun Tanks successfully completed the exercise. But the Army again came back with suggestions and modifications. In November 1997, the final list of suggested modifications and “joint Action Plan” for the implementation and certification was drafted. DRDO implemented the modification to the satisfaction of the Indian Army.

The Indian Amy again put the improved tanks to trials. The 43rd Armoured Regiment conducted the automotive trials. The trials were successful and Arjun tank was brought ready for full scale production.

The Arjun MBT project was successfully closed at Rupees 305 Crores. The final acceptance by the Indian Army led to placement of order for 124 Arjun Tanks in 2002.

DRDO transferred the design and other drawings to the manufacturing agency HVF in 2002.

The Authorised Holder of the Sealed Particulars is with DRDO till certain maturity level is reached in production, i.e, the first 30 tanks produced by HVF will have quality control certified by DRDO. After that Arjun Tank will be certified by DGQA.

Arjun is a sad case of the armed forces demanding a lot more from the DRDO than the foreign supplier. It kept changing the goal post all the time when it kept hearing and seeing newer systems.
Any weapons system takes a period of time to develop and optimize.
There should have been Arjun 1 in production ages ago with the original GSQR, then with newer systems and technologies coming through we could have had Arjun 2 and 3. Thats how all weapons systems go. The Abrams tank of today is not what it was during the first Gulf War. Nor is the F 16 of today same as that 30 years ago. It has been refined all the time adding newer technologies and capabilities. Same thing has happened to the LCA where the AF kept adding new requirements as a result of which the program got delayed, weight increased and therefore the original planned engine became obsolete due to its power output.

Indian Army has a new claim against the Arjun Tank. It claims that the engine of the Arjun Tank has failed four times. Before I get into the details further, its necessary that the background of this new claim has to be told.

Last year, Combat Vehicle Research Development Establishment (CVRDE, a unit of Defence Research and Development Organisation) was ready for a comparative trial between Indian Army’s imported T-90S and the license produced T-72 versus the home grown Arjun Tank as asked by army. The Indian Army officials realizing that the national media is scrutinizing the tanks performance, pulled out of the trials and went for a “accelerated usage cum reliability trial” (AUCRT).

The trials are for over 5 months and 5000 kms from November 2007. Out of this 2000 kms have been run in the below 40 degree centigrade (winter) conditions. Rest 3000 kms will be done in the above 40 degree centigrade conditions.

The AUCRT trials are army’s internal trials and hence is out of scrutiny of the media and the third parties. Right from the beginning of the (even before) trials, it was forgone conclusions about the color the Indian Army would give to the Arjun Tanks performance during the trials. Now since the trials were Army’s readiness for inducting Arjun tank, but, being the user, it has the right to comment about the performance of the tank in trials. As was expected this particular loophole seems to have been exploited by some officials. Here is a simple logic, if the Arjun Tank engine has a problem, simply replace it in 40 minutes flat and move on. Rectify the faulty engine and keep it as a stand by. Its very very simple. What actually happened was the transmission had a problem (something related to the ball bearings), which was rectified. The transmission is imported from the finest transmission maker in the world. Mind you, the tank did not stop for the reason, it got a different engine in 40 minutes and moved on. If the same transmission failure had happened in the imported T-90S tank of T-72 tank, it would have been grounded till the repairs were affected. So, Arjun Tank engine failure does not has same meaning as T-90S or T-72 engine failures. This is another loophole that is been used to exaggerate the engine issues of Arjun Tank.

Now the claim it failed 4 times has be be really proved by the concerned Indian Army officials. Four engines changes with just 1000 kms (by each tank) being run is bit too much for a knowledgeable person to digest.

The solution lies in third party auditing. Its high time we the tax payers know the truth.

During evidence before the Committee, a representative of the Army clarifying the position regarding performance of the Arjun tank submitted as under:-

“Sir, we have just carried out the trial in winter. The tanks have performed very poorly. There have been four engine failures so far. The tanks have done about 1000 km each. There has been a problem. The Defence Minister has been apprised by the Chief. I think two or three days back, he has written a DO letter giving the exact position. So a lot of improvements have to be done before the Army will be satisfied with the Arjun tank.”

The factual position

During the AUCRT in Pokhran, there was NO problem with either of the two engines. The problems were actually with four transmission systems: supplied by Renk AG, from Germany.

The problem: When the oil temperature went up, the oil viscosity was reduced… and the oil pressure was therefore insufficient. As a result, the bearing gave way, and the main shaft in the transmission also got damaged. Pieces were flying around and, when the transmission gearbox was opened, it looked pretty ugly.

The investigations are focusing on three aspects:

1. The possibility that the use of indigenous oil, rather than German oil, may have led to a failure of lubrication. The CQA (PP)… that is Controller of Quality Assurance (Petroleum Products)… has examined the oil and said that it is of the same grade as the foreign oil. However, the experts from Renk AG are still not convinced. They have taken samples of the oil to Germany to analyse, are will reach a conclusion by Monday, 21st April.

2. The possibility that recent changes made to the Arjun’s system of dual gear levers might have led to the problem. The driver has a Mode Selector Switch (with options: Forward-Neutral-Reverse)… and also a gear lever (with options: 1, 2, 3, Automatic). So totally, the tank has four forward and two reverse gears. Recently, when the production series tanks began being manufactured, the Gear Lever options were changed to (1, 2, Automatic). In the new system, gears 3 and 4 engage and disengage automatically. In fact, one school of thought amongst the designers is to have just the first gear manual… and then 2-4 automatic, i.e. (1, Automatic).

The CVRDE’s Transmission Group Team has recommended that another Manual Gear lever be introduced. That would be used while tow starting the tank. There are also problems with the logic of gear change in the Pokharan area where the tests are taking place. Unlike the Suratgarh desert, which had heavy sand, the Pokhran desert has hard, flat ground. Since the driving conditions are different, the logic for gear changing has to be different, and the micro-switches that signal the gear changes have to be calibrated differently.

3. There is also a possibility that a recent change in the supplier of the bearing that failed might have led to the problem. [Renk AG, which manufactures the gearbox, recently changed its bearing supplier.]

Experts from Renk AG are reaching the trial area and also CVRDE, Avadi, on 22nd April. Renk AG is one of the world’s most respected suppliers of transmission systems and it’s prestige is at stake here. A top Arjun designer says, “Renk’s prestige is at stake. I have no doubt they will fix the problem fast.”

Problems with four HSUs

The second problem that the Arjun faced was in some Hydro-pneumatic Suspension Units (HSUs). The Arjun has 7 road wheel stations on each side, which means that each tank has 14 HSUs. With two tanks participating in the trials, there were 28 HSUs that were effectively taking part. Of these, four HSUs failed.

One of them was a genuine failure, in which the HSU’s breather pipe got damaged and sand went in through that. The other three HSUs failed after 2000 km of running. HVF lays down a service life of 2000 km for each HSU, so that was predictable. This was not a problem at all.

It might also be noted that it takes just two hours to replace an HSU in the Arjun. This tank does not have a torsion bar suspension, in which replacing a road wheel station was a major undertaking.

Incidentally, the HSU has been an area where the Arjun’s designers have put in some really serious thinking. The terrain in Pokhran, which is flat and hard, generates in the HSU pistons a low amplitude, high frequency vibration. That is in contrast to heavy sand dune country like Suratgarh, where the HSU pistons undergo a high amplitude, low frequency vibration. In Suratgarh there were no problems, but the resurfacing of problems (albeit after the specified service life) in Pokhran brings to mind the earlier problems in which HSUs were leaking while the tank was being transported by train. The low-amplitude, high frequency vibrations generated by the vibrations of a train were enough to cause the HSUs to leak. That problem was resolved by changing the rings of the floating piston in the HSU. Also, the CVRDE tried out different types of piston rings, including imported ones from Hunger, Germany. Eventually, a life of 2000 km was achieved.

Problems with top rollers

Three or four top rollers also failed. That is being investigated.

Problems with tank Muzzle Reference Sight (MRS)

Of the two tanks undergoing AUCRT, one had a problem with the MRS, which was found to shift when the tank fired. This could have been easily overcome by firing through other means, disregarding the MRS. But suffice to say, the MRS had a problem.

These are very interesting dimensions to the trials in Pokhran, but far more interesting is the way the Army has reacted to them… taking the opportunity to slam the CVRDE for a “substandard” tank.

It has been confirmed that the Latin American country Colombia has expressed interest in purchasing India's indigenous Main Battle Tank (MBT) Arjun. The National Army of Colombia (Ejército Nacional de Colombia) operates armoured personnel carriers and infantry combat vehicles of Brazilian and American origin, but does not have any main armoured strength. As part of its modernisation drive, the country is interested in inducting regiments of main battle tanks. The country has sent the DRDO a request for information (RFI) on MBT Arjun. This is the first ever expression of interest from abroad in the MBT Arjun.

The Colombian Army apparently wants tank regiments to bolster defences on its border with Venezuela where the Chavez government is going on a relentless arms buying spree. In 2004, in fact, Spain pulled out of a deal to supply 46 AMX-30 battle tanks to Colombia amid fears that it would spark off an arms race with Venezuela -- which is precisely what has happened anyway. Remember, Colombia is a country embroiled in low intensity armed civil war, one that has been on since the 1960s.

Sir as far as the Arjun is concerned, the DRDO has got third party audit done and they say the audit shows that the tank is very good and consistent with international standard.
Of the equipment is faulty then it will be found out.